Fairfax, colloquially Central Fairfax, Downtown Fairfax, Fairfax City, or the City of Fairfax, is an independent city in the Commonwealth of Virginia in the United States. As of the 2010 census the population was 22,565, which had risen to an estimated 24,013 as of 2015.The city of Fairfax is an enclave within the separate political entity Fairfax County. The city of Fairfax and the area immediately surrounding the historical border of the city of Fairfax, collectively designated by Fairfax County as "Fairfax", comprise the county seat of Fairfax County. The city is part of the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area as well as a part of Northern Virginia. The city is 17 miles west of Washington, D.C. The Washington Metro's Orange Line serves Fairfax through its Vienna station, which is a mile northeast of the city limits. CUE Bus and Metrobus operate in Fairfax.